Monensin-resistant LLC-PK1 cell mutants are affected in recycling of the adenylate cyclase-stimulating vasopressin V2-receptor

David A. Jans, Patricia Jans, Heike Luzius, Falk Fahrenholz

Research output: Contribution to journalArticleResearchpeer-review

3 Citations (Scopus)

Abstract

The ionophore monensin was found to markedly reduce the rate of return of vasopressin V2-receptors to the membrane following down-regulation with [Arg8]vasopressin (AVP), as well as hormone dissociation (unloading) from cells following ligand binding and internalization in LLC-PK1 renal epithelial cells. Monensin-resistant LLC-PK1 mutants were isolated and characterized for V2-receptor recycling. Whilst the MN-41 mutant appeared to be impaired in [3H]AVP internalization, the MN-11 and MN-21 mutants exhibited parental V2-receptor binding and internalization, but markedly impaired receptor recycling subsequent to ligand-dependent receptor down-regulation. Unloading subsequent to ligand binding and internalization at 37°C was also much slower in the mutants either at 37°C or 23°C. In contrast, unloading subsequent to binding at 23°C, or to binding at 37°C in the presence of NH4Cl, was comparable in LLC-PK1 and mutant cells implying the active nature of the recycling process impaired in the mutants. The mutations conferring resistance to monensin thus concomitantly impaired V2-receptor recycling in the mutants. Results argue for a monensin-sensitive endosomal/lysosomal pathway for the renal V2-receptor, representing the first such report for an adenylate cyclase stimulating receptor.

Original languageEnglish
Pages (from-to)165-174
Number of pages10
JournalMolecular and Cellular Endocrinology
Volume81
Issue number1-3
DOIs
Publication statusPublished - 1 Jan 1991
Externally publishedYes

Keywords

  • Endocytosis
  • Monensin
  • Receptor recycling
  • Renal epithelial cell mutant

Cite this